JPH0541882B2 - - Google Patents

Description

Detailed Description of the Invention - Industrial Application Fields The present invention uses steam pipes to guide saturated steam generated by a steam generator to a heat radiating section, which gives latent heat to the surrounding fluid and generates heat. The condensate that has been discharged and condensed is temporarily stored, and then the heating of the steam generator is stopped to create a vacuum inside the steam generator,
The present invention relates to a steam generator used in a steam-type heat transfer means that utilizes this vacuum effect to reflux the condensed liquid into the steam generator and transfers heat by repeating this process.

●Prior art and its problems Steam generators commonly used in the past are designed to continuously generate steam while supplying water to keep the boiler liquid level approximately constant; The liquid is transferred to the heat dissipation section, gives latent heat to the object, and the condensed liquid is temporarily stored. When the amount of liquid in the steam generator decreases, the generation of steam is stopped and the steam is generated inside the steam generator. The condensate that is once stored in the heat dissipation section due to vacuum flows back into the steam generator under the action of atmospheric pressure, and then generates steam again to transport the thermal energy to the destination using steam pressure, and then The steam generator used in the method of refluxing condensate into the steam generator using the vacuum generated within the steam generator (hereinafter referred to as the intermittent vacuum reflux method) is A phenomenon that does not exist in general boilers occurs, in which the heat transfer area where the combustion gas flow and the liquid come in contact changes.

A kettle-type steam generator, as shown in Figure 7, can easily be considered as a steam generator used in the intermittent vacuum reflux method, but it not only has a low thermal efficiency of about 50%, but also has problems in terms of running costs. As the liquid volume decreases, the upper part of the container becomes more susceptible to overheating. If heat transfer fins are provided around the container to increase efficiency, heating of the container is further promoted. If the vessel is overheated, the steam generator will not be easily cooled even if the fuel supply is stopped, which will delay vacuum generation and prolong the reflux time of the condensate, which is a major disadvantage. That's a problem.

●Structure of the present invention The present invention eliminates the above-mentioned drawbacks.The structure of the present invention is to guide saturated steam generated by a steam generator to a heat radiation part using a steam pipe, and to transfer latent heat to the surrounding fluid at this heat radiation part. The condensed liquid is temporarily stored, and then the heating of the steam generator is stopped to form an empty room inside the steam generator, and the vacuum effect is used to remove the condensed liquid. In a steam generator used in a steam-type heat transfer means that recirculates water into the steam generator and transfers heat by repeating this process,
A steam generator body is positioned above the burner, a large number of heat transfer fins are welded to the outer circumference of the steam generator body, and a circulation guide plate is provided along the inner circumference to form a circulation path. Openings are provided at the bottom and top.

With the above configuration, the gas-liquid mixed-phase heating medium sealed in the steam generator is heated in the circulation path formed by the gap between the body and the circulation guide plate, and the heated heating medium is heated through the upper opening. The liquid flows out from the chamber in a gas-liquid mixed phase state, returns to the body, enters the circulation path again through the bottom opening, and repeats the cycle of being heated. As a result, a liquid film can be maintained on the inner surface of the body, which acts as a heat transfer surface, and overheating of the steam generator can be prevented while maintaining high efficiency.

●Embodiment FIG. 1 shows an embodiment of the present invention, and FIG. 2 shows a cross section taken along the line AA in FIG.

Reference numeral 1 indicates a burner, 2 indicates a fuel supply pipe, 3 indicates a solenoid valve installed in the middle of the fuel supply pipe 2, and 4 indicates a position facing the mixing pipe of the burner 1, and a valve located at the tip of the fuel supply pipe 2. This is the attached nozzle.

5 is a combustion chamber surrounded by an inner shell 6 and a steam generator body 7; 8 is a circulation guide plate;
is attached to form a circulation path 8' along the inner surface of the body 7, and has an opening 8'' at the bottom.
An upper opening 8 is formed in the upper part.

Reference numeral 9 is a bumping prevention plate that is located within the circulation path 8' and covers the bottom opening 8''. Reference numeral 10 is a large number of heat transfer fins that are welded to the outer periphery of the steam generator body 7. .11 is a low liquid level detection sensor, 12
13 is a high liquid level detection sensor, 13 is a temperature sensor, 17 is a heating medium liquid, 14 and 16 are an inlet valve and a discharge valve, respectively, for the heating medium 17, 15 is a pressure relief valve, 1
8 is a steam outlet.

19 is an exhaust collection guide, 21 is an exhaust fan, 2
2 is an electric motor; 20 is an exhaust pipe connecting the exhaust gas collection guide 19 and the exhaust fan 21;

Next, the operation of the above embodiment will be explained.

Initially, the interior of the steam generator 7 is filled with a heat transfer liquid 17. When the solenoid valve 3 is opened and fuel is supplied to the burner 1, the fuel is combusted in the combustion chamber 5, and when the combustion gas passes between the inner shell 6 and the steam generator body 7, the heat transfer fins 10 work. Heat is transferred to the heat transfer liquid 17 more efficiently.

Part of the heat transfer liquid 17' to which heat is transferred in the circulation path 8' between the inner surface of the body 7 and the circulation guide plate 8 evaporates, increasing the void ratio. A circulation force is generated based on the specific weight difference between the heating medium liquid 17 inside the body 7 and the liquid flowing upward in the circulation path 8' formed between the inner surface of the body 7 and the circulation guide plate 8 in a gas-liquid mixed phase state. , a liquid film is held on the inner surface of the body 7, which functions as a heat transfer surface.

After gas and liquid separation, the generated steam is led from the steam outlet 18 to a radiator through a steam pipe (not shown), exchanges heat with indoor air, condenses, and is temporarily stored in a liquid pot.

The separated saturated liquid flows down into the interior of the circulation guide plate 8. At the bottom of the circulation guide plate 8, there is a circulation guide plate 8.
A bottom opening 8'' is provided for communicating the inside of the circulation passage 8' with the inside of the circulation guide plate 8. 9 acts to prevent steam from protruding into the inside of the circulation guide plate 8 through this bottom opening 8''.

When the amount of heat medium in the steam generator decreases as the steam is sent out, the liquid level inside the circulation guide plate 8 decreases and the circulation force weakens. A liquid film is maintained on the inner surface of the body 7 until the temperature reaches about 20%, allowing efficient heat transfer, and also preventing overheating of the steam generator.

When the amount of the heat transfer fluid decreases to the point where the low liquid level detection sensor 11 detects a reduction in amount, a closing signal is sent to the electromagnetic valve 3 installed in the middle of the fuel supply pipe, and combustion is stopped.

When the steam generator is cooled, the steam inside it condenses to create a reduced pressure state, but the exhaust fan 21 continues to operate to shorten the cooling time. Note that the operation mode of the exhaust fan 21 may be set to increase the air volume during cooling to further enhance the cooling effect, thereby shortening the waiting time.

When the pressure inside the steam generator decreases below atmospheric pressure,
Due to the action of atmospheric pressure on the condensate stored in the liquid pot provided in the radiator, the heat medium flows back into the steam generator from the vessel outlet 18 through the steam pipe.
When the reflux amount reaches the high liquid level detection sensor 12, the solenoid valve 3 is opened to restart combustion.

The high liquid level detection sensor 12 does not need to be installed at the top of the steam generator because the temperature of the heat transfer liquid does not immediately reach the boiling point even after restarting combustion, reducing the time required to restart the steam. It is provided at an intermediate position for the purpose of

When the pressure inside the steam generator increases abnormally due to blockage of the steam pipe, etc., the temperature sensor 13 detects the abnormal increase in the saturation temperature and closes the solenoid valve 3. If a failure occurs in this safety circuit, the pressure relief valve 15 discharges steam to ensure safety.

FIG. 3 shows a second embodiment of the present invention, and FIG. 4 shows a cross section taken along line BB in FIG.

Reference numeral 23 is a gas-liquid separator installed in front of the steam outlet 18.

At the beginning of steam generation when the steam generator is filled with heat medium liquid, the liquid level of the heat medium liquid 17 inside the circulation guide plate 8 is high and the circulation force is excessive, so that the heat in the vessel liquid multiphase state is Although the medium tends to flow violently and not be sufficiently separated into gas and liquid and is sent into the steam pipe as a liquid phase from the steam outlet 18, by arranging the gas-liquid separator 23 in front of the steam outlet 18, the inside of the steam generator is This can prevent the influence of the intense flow of water from reaching the steam outlet 18.

FIG. 5 shows a third embodiment of the present invention, and FIG. 6 shows a cross section taken along line CC in FIG.

Reference numeral 23' indicates upper and lower communication pipes 24, 25.
A gas-liquid separator is attached to the steam generator body 7 via a gas-liquid separator apart from the one shown in FIGS. Sensor 11' is a low liquid level detection sensor. 18' is a vapor outlet provided at the top of the gas-liquid separator 23'.

By arranging the gas-liquid separator 23' in this way, the intense flow within the steam generator is difficult to be transmitted to the gas-liquid separator 23', and the gas-liquid separator 23' is partially in a gas-liquid mixed phase state.
Even if steam flows into the steam pipe 3', the vessel liquid separator advances further and only steam is sent out from the steam outlet 18' to the steam pipe.

●Effects of the present invention The present invention has the above-described configuration, and provides the following effects.

Since the heat medium in a gas-liquid mixed phase state flows in the circulation path formed between the inner surface of the steam generator body and the circulation guide plate, a liquid film is maintained on the inner surface of the steam generator body, which functions as a heat transfer surface. Therefore, the steam generator can stably generate steam with high efficiency without being overheated.

Since the inside of the steam generator is rapidly cooled after heating is stopped, a reduced pressure state can be created in a short time, and the reflux time can be shortened.

Since a large number of heat transfer fins can be arranged around the outer periphery of the steam generator body, high efficiency can be easily achieved.

If a gas-liquid separator or a gas-liquid separator is installed, it is possible to suppress sending out of the heat medium in its liquid phase at the initial stage of steam generation, so that the heat transfer time by steam can be lengthened.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional side view of a steam generator according to the present invention, FIG. 2 is a cross-sectional view taken along line A-A, FIG. 3 is a cross-sectional side view of a steam generator with a gas-liquid separator installed inside, and FIG. Figure 5 is a cross-sectional view of the steam generator with the gas-liquid separator located outside, and Figure 6 is a cross-sectional view taken along line B-B.
-C sectional view and FIG. 7 are sectional views of a conventional steam generator. DESCRIPTION OF SYMBOLS 1...Burner, 6...Inner shell, 7...Steam generator body, 8...Circulation guide plate, 8'...Circulation path, 8''...
...Bottom opening, 8...Top opening, 9...Bumping prevention plate, 10...Fin, 21...Exhaust fan,
23, 23'... Gas-liquid separator.

Claims (1)

[Claims] 1. Saturated steam generated by a steam generator is guided to a heat radiating part using a steam pipe, and the heat radiating part gives latent heat to the surrounding fluid and releases heat, and the condensed liquid is condensed. Once the liquid is stored, the heating of the steam generator is stopped to create a vacuum inside the steam generator, and this vacuum action is used to reflux the condensed liquid into the steam generator, and this process is repeated to transfer heat. In a steam generator used as a steam-type heat transfer means for carrying out A steam generator used in a steam heat transfer means, which is provided with a guide plate to form a circulation path, and has openings at the bottom and top of the circulation guide plate. 2. A steam generator used in the steam-type heat transfer means according to claim 1, wherein a gas-liquid separator is disposed in front of the steam outlet. 3. The steam-type heat transfer means according to claim 1, wherein the gas-liquid separator is attached to the body of the steam generator via an upper communication pipe and a lower communication pipe, and a steam outlet is provided at the top of the gas-liquid separator. A steam generator used in